Tuning for Higher idle RPM?

[Bucksath]

I tried doing a quick search but didn’t exactly find what I was looking for. So the hellcat/Melling oil pump seems to be the “fix” for low hot idle oil pressure but would tuning the hot idle in park engine RPM be a much easier solution? I’ve got a 2020 5.7 rebel and it idles at what looks like 550 RPM when at full operating temperature with 33 psi. Just lightly pressing the pedal and getting the RPM around 750 RPM increases the oil to 45 psi. It seems that you could just have a tuner increase the idle RPM to around 750 and solve the problem. Installing the Melling or hellcat oil pump is in my wheelhouse but it’s still quite an undertaking. I think that increasing the idle RPM in park would solve a lot of the low pressure problems. Does anyone have any thoughts on this or if you’ve done it? Thanks.

 

[Eighty]

I have zero productive input for you. Just curious why the idle pressure is such a concern for you. Do you spend long periods running the truck in park?

 

[Bucksath]

Well it seems that this is when all the damage is done. I guess my thought is wouldn’t that be a better/easier solution to the low oil pressure at hot idle problem. To be honest I don’t think I did spend that much time idling but my log shows 275 hours at idle with 38,xxx on the motor.

 

[2021QCBH]

I just turned 100 idle hours at 53k miles. I only remote start if the truck is iced over badly. Otherwise, I just remote start 30 seconds before walking out so it’s idled down and not going into gear at 1200 rpm’s.

 

[Eighty]

Well it seems that this is when all the damage is done. I guess my thought is wouldn’t that be a better/easier solution to the low oil pressure at hot idle problem. To be honest I don’t think I did spend that much time idling but my log shows 275 hours at idle with 38,xxx on the motor.

Just checked mine. 34 hrs of idle at 30k. Yeah, you spend a lot of time idling.

 

[kdoublep]

It's a good safeguard to have in place with a good lubrication/filter strategy. I see it as a good thing.

 

[Bucksath]

It's a good safeguard to have in place with a good lubrication/filter strategy. I see it as a good thing.

I do. I change oil every 5k and also rotate the tires. Wix XP filter and I run mobile 1 truck and suv oil. Man I guess I do have a lot of idle hours.

 

[Darksteel165]

Just checked mine. 34 hrs of idle at 30k. Yeah, you spend a lot of time idling.

Does it count time with the truck on but engine off? Mine shows a boat loaf of idle hours but I feel like I don't idle that often... I wonder what it determines as idle time.

 

[HSKR R/T]

Does it count time with the truck on but engine off? Mine shows a boat loaf of idle hours but I feel like I don't idle that often... I wonder what it determines as idle time.

It will only count hours with engine running.

 

[stevj]

Does it count time with the truck on but engine off? Mine shows a boat loaf of idle hours but I feel like I don't idle that often... I wonder what it determines as idle time.

Engine running but vehicle not in motion.
Sitting at a red light, etc.

Steve

 

[RAL]

I tried doing a quick search but didn’t exactly find what I was looking for. So the hellcat/Melling oil pump seems to be the “fix” for low hot idle oil pressure but would tuning the hot idle in park engine RPM be a much easier solution? I’ve got a 2020 5.7 rebel and it idles at what looks like 550 RPM when at full operating temperature with 33 psi. Just lightly pressing the pedal and getting the RPM around 750 RPM increases the oil to 45 psi. It seems that you could just have a tuner increase the idle RPM to around 750 and solve the problem. Installing the Melling or hellcat oil pump is in my wheelhouse but it’s still quite an undertaking. I think that increasing the idle RPM in park would solve a lot of the low pressure problems. Does anyone have any thoughts on this or if you’ve done it? Thanks.

If the truck is not indicating an oil pressure issue with a warning light, and the oil pressure gauge is not indicating any issue, then you have no issue. From a comparison of other vehicles we have owned and still own, I can tell you that 33 psi at idle when the oil is hot is actually in the higher range. Some of the Euro cars will go down to high single digits.

Other thing to note, and I am not sure how it works with the Ram but it is very unlikely that you can change the idle RPM. This is going to be set by the engine management computer based on the inputs it is receiving from various sensors.

As far as idle hours go, my understanding is that the idle hours is showing engine running but car not moving. On my truck, idle hours are slightly less than 10 percent of total engine hours. But I also make a point of not idling any of our vehicles if I can avoid doing so because I don't like to waste fuel. If you have to run more time idling, I would follow the severe service schedule in the manual and make a point of using a high quality, full synthetic motor oil. The synthetic oil will resist degrading more than a semi-synthetic blend. I would also stick with the 5w20 rating that is spec'd, as going down to 0w20 will only lower your hot idle oil pressure, even if only slightly (if this is something you are worried about).

HTH.

 

[BigFootGreg]

I am always waiting on the grandchildren for something and sitting in my truck while it's running. I keep an close eye on the oil pressure, it typically stays at 36 psi and I will touch the throttle every so often and it goes up to 45. So far I have not had any issues. 91000 miles. Run Penzoil Ultra Platinum 5-30.

Idle - 410
Drivings - 919
Total - 1329

Bigfootgreg

 

[JLaw297]

Did you find an answer to your original question? Can you raise the idle rpm via a Diablo tuner or do you need to get a custom tune via Jay Greene or someone like that?